Fixed location, ultra-low flush, sewage-holding vessel restroom system

ABSTRACT

A restroom system can include a fixed-in-place restroom building, a flush toilet housed in the restroom building, a water supply system in communication with the flush toilet, and a sewage-holding vessel in communication with the flush toilet. Sewage can be received in the flush toilet and water can be supplied from the water supply system to the flush toilet in an amount less than 1 gallon of water per flush. Sewage effluent can be flushed from the flush toilet, transported to the holding vessel, and extracted from the sewage-holding vessel and to a sewage hauling vehicle tank. The sewage effluent can be transported away from the restroom system in the sewage hauling vehicle tank.

RELATED APPLICATION

This application is a non-provisional application claiming priority toU.S. Provisional application No. 61/093,079, filed Aug. 29, 2008,entitled Fixed-in-Place Stand-Alone Flush Restroom, which isincorporated herein by reference.

TECHNICAL FIELD

The description relates to fixed-in-place restroom systems, and inparticular to the use of ultra-low volume flush toilets andsewage-holding vessels in such restroom systems.

BACKGROUND

Fixed building restrooms currently employ vault toilets, compostingtoilets, or conventional flush toilets. As used herein, fixed building,fixed-in-place, fixed location, and similar terms refer to restroombuildings being attached to a permanent foundation and/or partiallyplaced within an excavation. These terms can be contrasted with movablerestrooms, which can include standard “porta-potties”, mobile restrooms,restrooms mounted on trailers, floating restrooms, and the like. Arestroom building is a building whose primary features include restroomfeatures, such as toiletry, washroom, and/or shower features. Vaulttoilet buildings are equipped with toilet risers through which humanwaste and urine are deposited to a waste storage vault below, withoutmechanical assistance. Composting toilet buildings have a compostingchamber located below the toilet riser instead of a waste-holding tank.

These restroom options have advantages and disadvantages. Restroombuildings employing vault or composting toilets do not require water,sewer, or electrical service and thus are well suited to remotelocations, needing only heavy truck access for installation,maintenance, and waste removal. However, restrooms employing eithervault or composting toilets are vulnerable to users depositinginappropriate materials in them.

In addition, the public generally perceives vault toilets as beingunsanitary, smelly, and unsightly (being able to peer down at humanwaste in the holding tank). Debris and high concentrations of toiletpaper deposited in vaults makes pumping operations difficult,unsanitary, and expensive. Vault waste disposal is a problem in someareas due to its concentration of urine and waste and because toxicmaterials are sometimes added to reduce odors. The waste is concentratedbecause, unlike flush toilets, no water dilutes the waste. Many smallwastewater treatment plants are unable to process undiluted vault waste.Consequently, the waste must either be diluted or hauled to a largerwastewater treatment plant that can process undiluted sewage.

Occasionally, restroom buildings are equipped with composting toilets.These restrooms are very expensive to purchase and maintain. They arelabor intensive, frequently do not work, and potentially endangeremployees through pathogen exposure and confined space hazards.

Restrooms equipped with conventional flush toilets have none of thesedisadvantages. However, they require connection to a pressurized watersystem and to a sewer or on-site septic system. These utilities areoften unavailable in remote locations, are expensive to construct, andmay not be feasible. In many locations, flush restrooms also requireheat to keep the water lines from freezing. Accordingly, in locationsthat do not have water, sewage, or electrical services, flush toiletsmay be impractical and permanent restroom buildings are typicallyequipped with vault toilets. Conventional flush toilets and urinals haveenvironmental issues related to their use of large amounts of water.

In an effort to make vault toilet restroom buildings more acceptable tothe public, many fixed vault toilet restrooms have been designed to meetthe specifications of the “sweet smelling technology”, or “SST”,developed by the U.S. Forest Service over the past 20 years. The mainSST design features for these buildings include the following:

-   -   waste vaults made of plastic or sealed concrete;    -   large black plastic stacks that use solar gain and flue design        to create negative pressure in the sewage vaults, which in turn        creates a downdraft through the toilet riser to direct odors        away from the interior building spaces;    -   access to the sewage vault through an exterior manhole for        pump-out servicing (previously, vault toilets were pumped out        through the toilet riser);    -   provision of separate sewage vaults for each toilet riser in        order to eliminate cross-flow conditions wherein air passes down        one toilet riser, over the waste material below and then out        another toilet riser into the building; and    -   fresh air vents located to minimize the possibility of drafts        bringing odors up the toilet risers into the occupied spaces.

Moveable ultra-low volume flush toilet restrooms have been commerciallyavailable for many years. However, similar technology has not beendeveloped for application in fixed restroom buildings. Two examples ofportable toilet restrooms with self-contained sanitation systems (i.e.,sanitation systems that do not require sewer or on-site septic systems)include those manufactured by Water-Loo, Inc; and Turkstra. The reasonthese moveable restroom designs have never been adapted as fixedlocation restrooms appears to be primarily due to their high costper-use. The Water-Loo model was designed for railroad crews and isequipped with wheels set on the railroad tracks. The treated effluent isleaked onto the railroad tracks below. The cost per use is high, but forsuch specialized use this is not a primary concern. The Turkstraportable restroom is promoted as a portable golf course toilet wherehigh cost per use might be acceptable.

Joe Welch Companies, Inc. manufactures a self-contained moveable flushrestroom that is fitted with wheels and can be connected to aconventional trailer hitch for easy relocations. These units were firstdelivered in 1997 to the National Park Service at Lake Powell NationalRecreation Area. They were specifically designed by the engineeringstaff at Glen Canyon National Recreation Area for environmentalprotection as moveable units that could be located and relocated alongthe fluctuating shorelines of Lake Powell. Previously, single userportable vault toilets (of the kind used on construction sites) wereplaced on the lakeshore. These proved to be so unpopular that beachvisitors resorted to unsanitary practices in and near the water, causinghigh fecal coliform counts in the lake water. This led to multiple beachclosures. Accordingly, the moveable flush units were designed primarilyto protect the environment. In this unique situation, the possibility ofa relatively high cost per use was not a deterrent to their development.To date, it is believed that nearly all of the fully self-containedmoveable flush toilet restrooms built by Joe Welch Companies, Inc. havebeen purchased by the National Park Service, although some may have beenpurchased by individuals. Public marketing efforts by Joe WelchCompanies to sell these units appear not to have overcome customerperceptions that these units would be impractical due to high cost peruse.

The moveable self-contained waterborne sanitation restrooms that arecommercially available cannot take advantage of resource opportunitiesspecific to a site, such as alternative water and power sources. Forexample, the unit manufactured by Joe Welch Companies, Inc. cannot takeadvantage of available grid power or site supplied water. They cannot befitted with large capacity tanks or connected to sewage tanks that servemultiple restrooms. Furthermore, the units that are commerciallyavailable cannot function in freezing temperatures; they have novariability in architectural design or size; they have no flexibility onthe number of fixtures, or the types of fixtures, such as the additionof showers, sinks, or drinking fountains.

SUMMARY

There has long been a need for more pleasant permanent stand-alonetoilet facilities in locations not served by standard utilities. Thisneed is apparent from the significant effort that the U.S. Forestservice and others have put into making vault toilets more pleasant forusers. The SST design features reduce the odors within a vault toiletrestroom building. They do not eliminate the foul odors that occurexternally to the building in areas that are downwind. Despite thesignificant efforts of the U.S. Forest Service and others to improvevault toilet restroom buildings, the negative public perception of theserestrooms remains. Accordingly, there is, and has been for some time, asignificant need for fixed location restrooms that do not have thedrawbacks of vault and composting toilet systems in locations withoutsewer or on-site septic systems.

The present inventor has taken an entirely different approach to fillingthis need. While the development of remote fixed restroom buildings overthe past several decades has been focused on making vault toilet systemsbearable for users, and composting toilets practical, the presentinventor has shifted his focus to the development of waterborne toiletsystems for fixed restroom buildings with embodiments that can work evenin remote locations. Accordingly, the fixed location, ultra-low volumeflush, sewage-holding vessel restroom systems described herein representa significant advance in this area of technology that would not havebeen suggested or made predictable by prior systems.

According to one embodiment, a restroom system is provided. The restroomcan include a fixed-in-place restroom building, a flush toilet housed inthe restroom building, a water supply system in communication with theflush toilet, and a sewage-holding vessel in communication with theflush toilet. A sewage-holding vessel is a vessel (such as a tank orvault) that is configured to hold sewage effluent so that the sewageeffluent can be extracted from the tank and hauled away. Asewage-holding vessel is for holding sewage effluent to be hauled andthus does not include the septic features of a septic tank. The restroomcan derive its electricity from on-site resources without connection toa grid power system. Sewage can be received in the flush toilet, andwater can be supplied from the water supply system to the flush toiletin an amount less than 1 gallon of water per flush. Sewage effluent canbe flushed from the toilet bowl and transported to the sewage-holdingvessel, and extracted from the sewage-holding vessel to a sewage haulingvehicle tank. The sewage effluent can then be transported in the sewagehauling vehicle tank to a remote sewage disposal location.

According to another embodiment, a restroom system can include afixed-in-place restroom building and a flush toilet housed in therestroom building. The toilet can use less than 1 gallon of water perflush. A water supply system can be connected to supply water to thetoilet. In addition, a sewage-holding vessel can be in communicationwith the flush toilet to receive sewage effluent from the flush toilet.The sewage-holding vessel can include an outlet for extracting sewageeffluent from the sewage-holding vessel.

According to yet another embodiment, an existing vault or compostingtoilet restroom building can be retrofitted with one or more flushtoilets to produce a flush toilet restroom building. The retrofittingcan include replacing vault or composting toilet risers housed in afixed-in-place restroom building with flush toilets. The flush toiletscan be designed to use less than one gallon of water per flush, and canbe in communication with a sewage-holding vessel that was previously incommunication with the vault or composting toilet risers. An internal orexternal water supply system can be connected to the flush toilet, and aself-contained or grid power supply system can be connected to the flushtoilet restroom system.

This Summary is provided to introduce a selection of concepts in asimplified form. The concepts are further described below in theDetailed Description section. This Summary is not intended to identifykey features or essential features of the claimed subject matter, nor isit intended to be used to limit the scope of the claimed subject matter.The features described herein may be used separately or in combination.For example, many of the features described below, such as the featuresrelated to frost protection, may have uses other than in fixed-in-placerestroom systems with ultra low volume flush toilets. Similarly, theinvention is not limited to implementations that address the particulartechniques, tools, environments, disadvantages, or advantages discussedin the Background, the Detailed Description, or the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top sectional site and building plan view of a restroomsystem for Site #1, with most mechanical room equipment not shown.

FIG. 2 is a sectional view taken along line A-A of FIG. 1, with mostmechanical room equipment not shown.

FIG. 3 is a sectional view taken along line B-B of FIG. 1, illustratingmechanical room equipment.

FIG. 4 is a partially cut-away top view of a vault plan for the restroomsystem of FIG. 1.

FIG. 5 is a schematic wiring diagram illustrating electrical componentsand connections of the restroom system of FIG. 1.

FIG. 6 is a top site plan view of an alternative restroom system forSite #2.

FIG. 7 is a top building plan view of a restroom building in therestroom system of FIG. 6, with most mechanical room equipment notshown.

FIG. 8 is a sectional view taken along line C-C of FIG. 7, with mostmechanical room equipment not shown.

FIG. 9 is a sectional view taken along line D-D of FIG. 7, illustratingmechanical room equipment.

FIG. 10 is a top site plan view of an alternative restroom system forSite #3.

FIG. 11 is a top building and site plan view of an alternative restroomsystem for Site #4, with most mechanical room equipment not shown.

FIG. 12 is a sectional view taken along line G-G of FIG. 11, with mostmechanical room equipment not shown.

FIG. 13 is a sectional view taken along line H-H of FIG. 11.

FIG. 14 is a sectional view taken along line I-I of FIG. 11,illustrating mechanical room equipment.

FIG. 15 is a schematic wiring diagram illustrating some electricalcomponents and connections of the restroom system of FIG. 11.

FIG. 16 is a flow diagram illustrating general techniques relating tofixed-in-place stand-alone flush restroom systems.

FIG. 17 is a flow diagram illustrating general techniques relating toretrofitting existing restrooms to form fixed-in-place stand-alone flushrestroom systems.

The description and drawings may refer to the same or similar featuresin the same or different drawings with the same reference numbers.

DETAILED DESCRIPTION I. Fixed Location, Ultra-Low Flush Restroom SystemFeatures

Prior fixed-in-place flush restroom buildings have required a watersystem and either a sewer or septic system. If there is a potential forfreezing, building heating is required. Thus, such restrooms have notbeen used in many remote locations. The described embodiments providerestroom features that allow flush toilet restrooms to operate almostanywhere that has motorized vehicle access. These features can includeultra-low volume flush toilets and sewage holding vessels. The ultra-lowvolume flush toilets can produce a low amount of sewage effluent to bestored in the holding vessels and hauled away. Such toilets can also usea low amount of water. The restroom systems may also provide freezeprotection without the need to heat the restroom buildings. In someembodiments, restroom systems may also contain one or more of thefollowing features:

-   -   waterless urinals;    -   devices that prevent sewage spills and overflows;    -   water-holding tanks;    -   equipment that pressurizes water for flushing toilets;    -   equipment that pressurizes air for flushing toilets;    -   in-ground tanks, vaults, or basements for containment of water,        sewage, or equipment;    -   power derived from grid power, solar array(s), wind turbine(s),        storage batteries, mini-hydro, on-site combustion generators, or        a combination thereof;    -   water provided by connection to an existing on-site potable        water system; by connection to an on-site irrigation system; by        collection of ground water, surface water, or rainwater; by        hauled water; or by any combination thereof;    -   flue stacks for ventilation;    -   mechanical equipment that enhances or controls ventilation;    -   systems designed to prevent freezing of the water system;    -   maintenance features such as pump-out and fill piping; gauges or        indicators that show water levels, sewage levels, and battery        charge; and automatic door locks for times that the restroom        needs to be closed (i.e. after dark in public parks; when        holding vessel is full; when water tank is empty; when        electrical power is disrupted; when water pressure is lost;        etc.);    -   septic tanks that treat sewage prior to hauling;    -   porta-potty disposal and washdown sinks, fixtures, and        drainboards;    -   water conserving faucets and sinks, such as those that turn off        automatically after a short period of time;    -   water purification devices to remove pathogens from untreated        water;    -   water conserving showers, such as those that turn off        automatically after a short period of time; and    -   communal men's and women's rooms equipped with multiple fixtures        and with privacy partitions.

In some embodiments, restroom systems may be entirely new constructions.However, in other embodiments, existing restroom buildings such as vaultor composting restroom buildings may be converted to fixed location,ultra-low volume flush, sewage holding vessel restroom systems. Therestroom systems and restroom buildings may be put to non-residentialuse in non-residential settings, such as in campgrounds, golf courses,etc.

The fixed location, ultra-low volume flush, sewage holding vesselrestroom systems described herein can avoid drawbacks of vault andcomposting toilet building systems. The described restrooms can besubstantially odorless, both internally and externally. They may beimplemented without existing water service or connection to an on-siteseptic system or public sewer, which are used for conventional flushtoilet restrooms. They can produce highly conserved sewage effluent thatis less likely to have trash and chemicals, and that can often beeconomically hauled to standard sewage treatment facilities, typicallywithout alteration or dilution. The restrooms described below may beimplemented without installing new utility service lines or systems, andthey may utilize existing on-site power resources and water resources(supplemented by hauled water if needed).

II. Factors Pointing Away From Fixed Location, Ultra-Low Flush SewageHolding Vessel Restroom System

Several factors would have pointed those in the fixed location restroomindustry away from developing, marketing, or deploying a fixed location,ultra-low volume flush, sewage holding vessel restroom system. Thus,doing so would not have been suggested by or predictable from priorrestroom systems. However, the present inventor has made severaldiscoveries, which reveal that—contrary to the accepted wisdom in theindustry—fixed location, ultra-low volume flush, sewage holding vesselrestroom buildings are feasible and desirable. To understand why thosein the industry would have been pointed away from fixed location,ultra-low volume flues, sewage holding vessel restrooms, the followingshould be considered:

-   -   A. The industry that specializes in the science of        self-contained fixed location toilet buildings is largely        unaware of developments in mobile ultra-low volume flush toilet        technologies.    -   B. The industry that specializes in the science of        self-contained fixed location toilet buildings would assume that        self-contained flush restroom buildings would require hauling        copious amounts of sewage effluent and flush water and would        therefore be too expensive to be practical.    -   C. The industry that specializes in the science of        self-contained fixed location toilet buildings (vault and        composting) would assume that self-contained flush toilet        restroom buildings have significantly higher construction        (capital) costs than vault or composting toilet buildings.    -   D. The industry that specializes in the science of        self-contained fixed location toilet buildings (vault and        composting) would assume that a potable water supply would be        required for a flush toilet system.    -   E. The industry that specializes in the science of        self-contained fixed location toilet buildings (vault and        composting) would assume that self-contained flush toilet        restroom buildings need to be heated to prevent freezing of the        water system in locations subject to freezing temperatures        during the use season.    -   F. Making a self-contained flush toilet restroom building        practical and applicable to a variety of site conditions may        require many different design solutions, many of which are not        intuitive.

These factors and some of the present inventor's discoveries that helpedhim overcome these factors are discussed below.

A. The industry that specializes in the science of self-contained fixedlocation toilet buildings is largely unaware of developments in mobileflush toilet technology.

The community that specializes in fixed location restroom buildingsdeals with a market dominated by campgrounds, parks, and highway restareas. It is far removed from the community that designs mobile flushtoilet systems for RV's, buses, trains, airplanes, and boats; whereminimizing water usage has become a science unto itself. Therefore, thefixed location restroom industry has remained unaware of theapplications of ultra-low volume toilets and waterless urinals that aredurable enough for public use and that can drastically reduce the costof pumping and hauling sewage.

B. The industry that specializes in the science of self-contained fixedlocation toilet buildings would assume that self-contained flushrestroom buildings would require hauling copious amounts of sewageeffluent and flush water and would therefore be too expensive to bepractical.

The inventor has discovered that through the use of ultra-low volumeflush toilets and waterless urinals the amount of water needed for aflush toilet restroom can be reduced by approximately 90%, and theamount of sewage produced can be reduced by approximately 86%, whencompared to standard low flow flush toilets and urinals. Table A and Bbelow compare the amounts of water used and sewage effluent produced by1000 typical uses where a public restroom building is equipped with 1quart per flush toilets, such as the Microphor model LF520 toilet, andwaterless urinals, instead of standard “low volume flush toilets andurinals.” The Site #1 restroom building illustrated in FIGS. 1-4 anddiscussed below can have a sewage-holding tank capacity of 2,335gallons. If this restroom is equipped with one quart per flush toilets,then the capacity of the sewage-holding tank can be 8,876 uses. In somelocations this can represent an entire use season, requiring only onepumping per year, which is the maximum time interval recommended forpumping vault toilets.

TABLE A ESTIMATED SEWAGE GENERATED AND WATER USED WITH MICROPHOR FLUSHTOILETS (1 quart per flush) AND WATERLESS URINALS, PER 1000 USES vol./element use unit uses volume unit # 2 (bowel water 0.375 gallons 200 75gallons movement) waste 0.08 gallons 200 16 gallons urine 0.04 gallons200 8 gallons # 1 (urine only) water 0.25 gallons 400 100 gallons femaleurine 0.08 gallons 400 32 gallons # 1 (urine only) urine 0.08 gallons400 32 gallons male TOTAL 16 gallons WASTE TOTAL 72 gallons URINE TOTAL175 gallons WATER TOTAL 263 gallons EFFLUENT * Table shows a # 2 userequiring more flush water than a # 1 use. This is due to the assumptionthat # 2 usage will sometimes require more than one flush.

TABLE B ESTIMATED SEWAGE GENERATED AND WATER USED WITH STANDARD “LOWVOLUME” FLUSH TOILETS & URINALS, PER 1000 USES vol./ element use unituses volume unit # 2 (bowel water 2.4 gallons 200 480 gallons movement)waste 0.08 gallons 200 16 gallons urine 0.04 gallons 200 8 gallons # 1(urine only) water 1.6 gallons 400 640 gallons female urine 0.08 gallons400 32 gallons # 1 (urine only) water 1.6 gallons 400 640 gallons maleurine 0.08 gallons 400 32 gallons TOTAL 16 gallons WASTE TOTAL 72gallons URINE TOTAL 1760 gallons WATER TOTAL 1848 gallons EFFLUENT *Table shows a # 2 use requiring more flush water than a # 1 use. This isdue to the assumption that # 2 usage will sometimes require more thanone flush.

In addition, flush toilet effluent is typically significantly lessexpensive to pump out and dispose of than vault waste. Hauling costs maybe further reduced if the flush toilet effluent is hauled to a nearbylocation served by a sewer manhole or septic drain-field system, whichare options not typically available for vault waste. Additionally, thequantities of water delivered by hauling can be reduced or eliminated byusing on-site non-potable water, such as rainwater, ground water,surface water, or irrigation water.

C. The industry that specializes in the science of self-contained fixedlocation toilet buildings would assume that self-contained flush toiletrestroom buildings have significantly higher construction (capital)costs than vault toilet buildings.

Vault toilet restroom buildings typically have no mechanical elements.The self-contained restroom buildings described below have ultra-lowvolume flush toilets involving electrical and mechanical operators andcontrols. Additionally, they may be equipped with waterless urinals,solar arrays, batteries, water pumps, accumulator tanks, temperaturecontrolled ventilation dampers, water tanks, gauges, controls, etc.Those in the industry would therefore assume that the construction costsfor self-contained flush toilet restroom buildings would be higher thanrestroom buildings equipped with vault toilets.

However, the present inventor has discovered that vault toilet buildingscan require more floor space per toilet than the restrooms describedbelow. This is particularly true when the vault toilet buildings arebuilt per SST guidelines, which require separate toilet rooms, fluestacks, vaults, and access manholes for each toilet. Many flush toiletscan be accommodated under one roof in some embodiments, such as Site #3discussed below, creating an economy of scale that can result in lowercapital costs per toilet than for vault toilet buildings. Reducing theamount of floor space per toilet can significantly reduce the overallcost because it is believed that the toilet building alone can representas much as 60% of the capital costs for the ultra-low volume flushtoilet buildings described herein. As additional toilets and urinals areadded under one roof, the restroom building remains mechanically thesame except for the additional flush toilets and urinals. Thus, there isan economy of scale with the restroom systems described herein, with thecapital cost per toilet decreasing with the number of toilets installed.

Additionally, the present inventor has discovered that some existingvault toilet buildings can be economically converted to waterbornerestroom systems according to embodiments described below, such as Site#4. Once converted, the vault toilet building can become a restroombuilding served by ultra-low volume toilets, and possibly with waterlessurinals. Converting the existing vault or composting restrooms could bemuch less expensive than constructing new flush toilet buildings whereowners desire this improvement.

D. The industry that specializes in the science of self-contained fixedlocation toilet buildings (vault and composting) would assume that apotable water supply would be required for a flush toilet system.

Conventional thinking is that public flush toilet buildings requireconnection to public water systems. In some locations this is notpossible or may be very expensive to install and maintain. However, forthose embodiments described herein where restrooms are without plumbingfixtures for drinking, bathing, or hand washing, potable water is notrequired. For those embodiments where plumbing fixtures for drinking,bathing, or hand washing are provided, a non-potable water supply can beused, provided the restroom is equipped with a water purification systemthat removes pathogens. Thus the embodiments described herein mayoperate without a potable water supply.

E. The industry that specializes in the science of self-contained fixedlocation toilet buildings would assume that self-contained flush toiletrestroom buildings need to be heated to prevent freezing of the watersystem in applications subject to freezing temperatures during the useseason.

Conventional thinking holds that preventing freezing of the water supplysystem would require heat produced by grid power, combustion powergeneration, natural gas heat, or propane heat. In many locations, gridpower and natural gas are not available. Combustion power generation andpropane heating have several drawbacks. For example, they require gasstorage and have environmental, security, cost, and safety issues.However, as described herein, the present inventor has discoveredseveral ways to protect the water supply system from freezing withoutresorting to conventional heating methods. These methods includecontrolling and limiting exterior/interior air exchange; capturingground heat through heat exchanged under the building or through thewater vault; circulation of ground conditioned air through themechanical room and under and around the toilet bowls; and automaticflushing of the toilets when the water in the bowls approaches freezingtemperatures.

F. Making a self-contained flush toilet restroom building practical andapplicable to virtually any site condition requires many designsolutions, many of which are not intuitive.

Those in the fixed-in-place restroom industry would have been deterredfrom developing self-contained water-borne restroom buildings because ofthe many issues that would need to be addressed, including waterconservation, reducing hauling costs, spill prevention, power supply,mechanical operators and controls, freeze protection, waterpurification, and pressurizing water. The present inventor has foundways to address these issues in comprehensive designs, as describedbelow with reference to several examples of restroom systems.

The present inventor has discovered that for fixed location flush toiletrestroom buildings to be practical in areas not fully served by sewers,potable water, and grid power, several desirable features can beaddressed by design. They include minimizing water usage and sewageproduction and providing on-site sewage effluent storage. The system canalso include other features, such as system controls, a building that isessentially odor free inside and outside, and safeguards to preventsewage spills. Components and sub-systems of the described system can beincluded to address the design features listed above. These componentsand sub-systems can include ultra-low volume flush toilets (using lessthan 1 gallon per flush), leak resistant sewage tanks or vaults, andmechanical and electrical systems and controls. These flush toiletfeatures have not previously been suggested or otherwise madepredictable for fixed-in-place restrooms. Instead, the resources thathave gone into improving fixed restrooms in remote locations over thepast several decades have focused on improving vault and/or compostingtoilet restroom systems.

III. Restroom System Embodiments at Various Sites

The described restroom system embodiments may be utilized incombinations that are customized for the specific site conditions and/orthe needs of specific users or site owners. Generally, the combinationof embodiments may capitalize on the existing assets for each site. Forexample, if a potable water system is not available, then the bestalternative water source could be hauled water or an on-site source suchas ground water, surface water, irrigation water, or rainwater, or acombination thereof. If grid power is not available at the site, thenthe marginal power needs of the restroom could be supplied by solararray(s), or by storage batteries, which are periodically rotated withnew batteries or batteries that have been charged off-site. If frostprotection is desirable at a particular location, it can be providedwithout heating the building.

Since there are many possible combinations of embodiments of thedescribed restroom system, and many possible floor plans, it is notpractical to include drawings of all possible options. The embodimentsdescribed below will make it apparent to persons skilled in this area oftechnology that they may implement different combinations of features,depending on the available resources at the site. The drawings anddescription below demonstrate that restroom buildings as describedherein can be configured to provide affordable and practical service inlocations where the current accepted wisdom in this technology areawould suggest that a flush toilet restroom is impractical, and thatvault toilet or composting toilet restroom buildings are the onlyreasonable option. To this end, details are provided herein that addressembodiments for four different site conditions.

It should be noted that the subject matter defined in the appendedclaims is not necessarily limited to the benefits described herein orthe details of particular embodiments. A particular implementation ofthe invention may provide all, some, or none of the benefits describedherein. Although operations for the various techniques may be describedherein in a particular, sequential order for the sake of presentation,it should be understood that this manner of description encompassesrearrangements in the order of operations, unless a particular orderingis required. For example, operations described sequentially may in somecases be rearranged or performed concurrently. Techniques describedherein with reference to flowcharts may be used with one or more of thesystems described herein and/or with one or more other systems.Moreover, for the sake of simplicity, flowcharts may not show thevarious ways in which particular techniques can be used in conjunctionwith other techniques.

A. Site#1

This hypothetical location has no available sewer or septic system, nogrid power, and no on-site water source. The location may be subjectedto periodic sub-freezing temperatures during the use season. It doeshave good solar exposure and ample precipitation. In this case, theconfiguration of the restroom building chosen by the designer and ownermight be as depicted in FIGS. 1-5.

The illustrated restroom system (100) can include a building (102) withapproximately 97 square feet of interior space, although many differentconfigurations and/or sizes of restroom buildings could be used. Thebuilding (102) can include a floor (104), a front exterior wall (106), apair of side exterior walls (108), a rear exterior wall (110), and aroof (112).

The building (102) can include two toilet rooms (120) that can be mirrorimages of each other, however in this example they are not equipped thesame. Each toilet room (120) can be defined by the rear exterior wall(110), a side exterior wall (108), the front exterior wall (106), and aside interior wall (122) that extends from the front exterior wall (106)back to the rear exterior wall (110), and between the floor (104) andthe roof (112). The toilet rooms (120) can each be equipped withstandard grab bars (124) and may have a turning radius (126) sufficientto accommodate a wheelchair, such as a 5 foot turning radius.

The building (102) can also include a mechanical room (128) between thetwo toilet rooms (120). The mechanical room (128) can be defined by theside interior walls (122) and the front and rear exterior walls (106,110). The mechanical room (128) can extend from the floor (104) to amechanical room ceiling (132), which can divide the mechanical room(128) from a mechanical room attic (134). The mechanical room attic(134) can be located directly above the mechanical room (128) and can bedefined by the front and rear exterior walls (106 and 110), the sideinterior walls (122), the mechanical room ceiling (132), and the roof(112). The building (102) can also include toilet room doors (140) and amechanical room door (142) in the front exterior wall (106).

Each toilet room (120) can house an ultra-low volume flush toilet (150)located adjacent to the interior side wall (122) of the toilet room(120). Toilet operators or controls (152), which are devices used tooperate the toilet (150), can be incorporated into the toilet (150)and/or located near to or remotely from the toilet (150). Such operators(152) can include a control system; a connection to an electric powersupply system; and a connection to a water supply system. The toiletscan be any ultra-low volume flush toilets (i.e., toilets using less thanone gallon of water per flush), such as a flush toilet using less thanabout 0.75 gallons per flush or less than about 0.5 gallons per flush.In one embodiment, the toilet (150) can be a Microphor model LF320stainless steel toilet available from Microphor of Willits, California,which can be set to use between 0.25 and 0.5 gallons per flush. In oneembodiment, the operators (152) can be standard operators also availablefrom Microphor for the LF320 model. These operators (152) can beconfigured in a conventional manner according to standard techniques,such as those set forth in installation instructions from Microphor. Onetoilet room (120) is shown equipped with a sink (153); a paper toweldispenser (154); a waste container (155); and a urinal (156) such as thewaterless urinals available from Waterless Co. under the name Del Marmodel 2901. The waterless urinals (156) can be installed and configuredin a conventional manner, per the manufacturer's instructions fromWaterless Co.

The restroom system (100) also includes a sewage storage system (158),which can include one or more sewage-holding vaults or tanks (160).Holding vessels, such as the holding vaults (160) hold sewage effluentto be hauled away, but the vessels do not include septic treatmentfeatures within the vessel. However, in some embodiments sewage effluentmay receive primary treatment by passage through a septic tank or otherseptic treatment device before being removed by hauling. In theillustrated example, the sewage storage system (158) includes onesubterranean sewage-holding vault (160) for each toilet room (120), withthe vault positioned beneath the rear portion of the associated toiletroom (120). Each toilet (150) and urinal (156) can be configured todrain into the associated sewage-holding vault (160) so that the vault(160) receives the sewage effluent from that associated toilet room(120). Each sewage-holding vault (160) can be accessed through avapor-tight cover (161) of a manhole in the sewage-holding vault (160).Alternatively, the restroom system (100) could include just onesewage-holding vault (160), and it could be located somewhere other thanbeneath the building (102).

The sewage-holding vault (160) can be a subterranean precast concretesewage-holding vault (160), and can be equipped with an impermeableliner or coating (162) to seal the vault. The sewage storage system(158) can also include standard sewage pump-out piping (164) that isconfigured to mate with sewage pump-out equipment associated with asewage transportation vehicle, such as by having a standardquick-connect feature. Each sewage-holding vault (160) can be vented bya small vertical pipe (166) that extends up from the sewage-holdingvault (160) and through the roof (112) of the building (102).

Each sewage-holding vault (160) can be equipped with one or morestandard float switches to alert operators and/or disable the flushingsystem if the sewage-holding vault (160) becomes too full. For example,each sewage-holding vault (160) can include a float switch or levelsensor (167) connected to a device (168) to alert an operator that thesewage-holding vault (160) should be pumped out soon. This device (168)can be an indicator light, a level indicating gauge, or a signaltransmitter (168). Each sewage-holding vault (160) can also include ahigher level float switch (169) that can activate an electric lock onthe toilet room doors (140) and/or shut down at the water supply system(170), which is part of the restroom system (100), before the effluentin the sewage-holding vault (160) can overflow. These float switches andthe corresponding control circuitry will be described in more detailbelow.

The water supply system (170) can supply pressurized water to thetoilets (150). The water supply system (170) can include a water storagevault (172) beneath each of the toilet rooms (120), such as asubterranean water storage vault (172) which can have an impermeableliner (173). The building can be equipped with a rainwater collectionsystem (174) which can include standard rain gutters (176), as well asstandard downspouts (178) leading into the water storage vaults (172).The water supply system (170) can also include water fill piping (180),which can be standard piping for receiving additional water tosupplement collected rainwater. For example, the water fill piping (180)can be configured to connect to a water-hauling vehicle. The watersupply system (170) can also include a water pressurization system (182)that includes a water pump (184) connected to draw water from the waterstorage vault (172) and feed it into an accumulator tank (186), which isconnected to the toilets (150) and sink (153) to supply pressurizedwater. The water pump (184) can be a standard water pressurizing pump,such as a “Classic 2088” water pump available from Shurflo, and theaccumulator tank (186) can be a standard tank, such as a 3400-002 tankavailable from Shurflo. The water system can be equipped with a waterpurification system (188), such as the “Water-fixer, model 500” todeliver pathogen free water to the sink (153). In addition, the waterstorage vaults (172) can have block-outs (190) high on their side wallsthat allow excessive rainwater or filling water inflows to spill out ofthe vault, thus preventing overfilling of the water storage vaults(172). The water supply system (170) also includes water lines (192)that connect the various other components of the water supply system.

The restroom system (100) can also include a power supply system (210)that includes a solar panel (212), such as the model GEPV-50 solar panelavailable from General Electric. The power supply system (210) can alsoinclude a controller (214), such as the 12 volt, 15 amp controllerequipped with a digital voltage meter available from Prostar. The powersupply system can also include one or more standard storage batteries(216), such as two MK model 8G27 storage batteries. The restroom system(100) could have as few as one battery, or several batteries, dependingon what the owner wants, as well as the electrical demands and the powersource. The storage batteries (216) can be connected in a conventionalmanner to be recharged by the solar panel (212), to supply the powerneeds of the restroom system (100). The solar panel (212) can be mountedon top of a flue stack (218) that extends up along the rear exteriorwall (110). For example, the solar panel (212) can be mounted with arotatable base (220), which allows a user to pivot the solar panel (212)to face in a desired direction (such as south when in the northernhemisphere) no matter what the building orientation is.

The restroom system (100) can include a frost protection system (230).The frost protection system (230) can include one or more of severalcomponents to protect the restroom system (100) from freezingtemperatures. For example, the frost protection system (230) can includebuilding insulation in the exterior walls (106, 108, and 110) and theroof (112); insulation around plumbing equipment such as the water pump(184) and the accumulator tank (186); and/or water lines (192) that donot break when frozen.

During use, the ventilation for the restroom building (102) can bepassively enhanced by the influence of the flue stack (218). The fluestack (218) can be vented through the grill (234) into the mechanicalroom attic (134). As air flows over the top of the flue stack (218), theventuri effect can create negative pressure in the stack (218), which inturn creates negative pressure in the unducted portion of the mechanicalroom attic (134). Relief air into the mechanical room attic (134) can besupplied from the toilet rooms (120) via the return ventilation grills(236). Relief air can be supplied into the toilet rooms (120) from theoutside as described below. Thus, air can be circulated to continuallyprovide fresh air to the toilet rooms (120), so long as there is airflowing over the flue stack (218).

In this example for site #1, the frost protection system (230) caninclude a passive heating and ventilation system (232) that controls airinto the building (102) and collects energy from the earth whenrequired. When outside temperatures are above freezing, freshunconditioned air from outside can flow through the building (102)through a series of grills and ducts. When outside sub-freezingtemperatures occur the air flow can be limited to air with temperaturesthat have been moderated by energy absorbed from the earth.

When outside temperatures are above freezing, air flow can be sequencedas follows: air is drafted up the flue stack (218) having flowed fromthe mechanical room attic (134) through a flue-to-attic grill (234) inthe rear exterior wall (110); having flowed from the toilet rooms (120)to the mechanical room attic (134) through a pair of ventilation grills(236) located in the side interior walls (122); having flowed from theoutside to the toilet rooms (120) through ventilation grills (238) andsupply ducts (240) in the side interior walls (122) and through amechanically controlled damper (250) location high on the front exteriorwall (106).

When outside temperatures drop below the set point of an externalthermostat switch (252) the mechanically activated damper (250), such asmodel CD50 damper available from Ruskin, can be activated and closed.When this happens, unconditioned outside air no longer flows through thebuilding (102) according to the airflow described above. When the damper(250) is closed air flow can be sequenced as follows: air is drafted upthe flue stack (218) having flowed from the mechanical room attic (134)through a flue-to-attic grill (234) in the rear exterior wall (110);having flowed from the toilet rooms (120) to the mechanical room attic(134) through a pair of ventilation grills (236) located in the sideinterior walls (122); having flowed from the mechanical room (128)through ventilation openings (260) in each toilet's (150) metal housingand through the interior space between each toilet's (150) metal outerhousing and inner metal toilet bowl and through the mechanical accesshole (262) at the back of each toilet (150) in the mechanical room wall(122); having flowed from the outside through floor grates (268) in themechanical room floor (104) through exhaust ventilation chases (270)cast in the walls of the water storage vaults (172) through a serpentineroute through the plenums (276) beneath the bottom of the water storagevaults (172) through intake ventilation chases (280) cast in the wallsof the water storage vaults (170) through intake grates (282) that areexposed to the outside air. This routing can provide conditioned reliefair that is influenced by the ground temperatures found in and under thewater storage vaults. As this air travels through the mechanical room(128) and through the space under and around the bowls of the toilets(150) it can help keep the toilets (150) and the components of the watersupply system (170) in the mechanical room (128) from freezing.

The plenum (276) can be created under the water vault liner (173) byframing (286), such as wood or metal framing, on a concrete floor (288)of the water storage vault (172). A plate (292), such as a steel plate,can be located on top of this framing, and the bottom of the tank liner(173) can rest on this horizontal plate (292). The horizontal plate(292) can extend from wall to wall in both directions. Each verticalchase (270 and 280) can be enclosed by a vertical plate (296), such as ametal plate, covering the exposed vertical face of the chase (270)extending downward from the respective grates (268, 282) to the top ofthe plenum (276). The framing (286) under the horizontal plate candirect air flowing through the plenum (276), forcing the air to travel aserpentine route. This serpentine route can increase mixing and contacttime of the air with the metal plate (292) above and the concrete vaultfloor (288) below. During freezing weather this process can conditionthe air by raising its temperature. A plenum drain (298) can be locatedin the vault floor (288) near the center of this plenum space (276) toallow any condensation to seep out. A similar plenum and venting systemcan be installed in the sewage storage tank to increase air flow, but itis not illustrated in the drawings. This type of venting system (232)can be useful aside from its use with the described restroom systems.For example, this type of venting system could be used for generalheating and cooling of a general purpose building. Referring to FIG. 5,the electrical components of the restroom system (100) are illustratedin a schematic wiring diagram. As can be seen, the solar array or panel(212) and the batteries (216) can be connected by positive and negativeleads to the battery charge controller (214), which regulates thecharging of the batteries (216) by the solar panel (212) and the outputof power from the batteries (216) to the other electrical components.The batteries (216) can output 12 volt power, although other voltagescould also be used, depending on the batteries and the needs of theother electrical components. If the electrical components have differentvoltage needs, then standard power converters can be used, as needed.

Power to a damper controller (310), which controls the damper (250), canbe routed through a standard 12 volt DC-to-24 volt DC power converter(308), such as a Solar Converter Inc, model EQ122420 converter, if thedamper controller is a 24 volt device. An exterior mounted thermostatswitch (252), such as a standard thermostat switch found in a typicalRV, can be mounted on the exterior rear wall (110) or some other placeoutside the building (102), and can be wired to close the circuit andpower the damper actuator or controller (310), such as a Belimo modelTF24 actuator, to close the damper (250) when the outside temperaturereaches a predetermined low set temperature. The thermostat switch (252)can open the circuit to allow the damper (250) to open when the outsidetemperature reaches a predetermined high set temperature.

The lower-level alert float switch (168) in the sewage-holding vault(160) can be wired to close a circuit to power an indicator light orgauge (320) when the level of the sewage effluent in the sewage-holdingvault (160) is at or above the alert float switch (168). Thus, the alertfloat switch (168) and the indicator light or gauge (320) can indicateto maintenance personnel that sewage effluent should be pumped out ofthe sewage-holding vault (160). The higher level float switch (169) canbe wired to open a circuit to shut off power to the water pump (184) ifthe level of the sewage effluent in the sewage-holding vault is at orabove the level of the shut-off float switch (169). In addition to, orinstead of, shutting off power to the water pump (184), the shut-offfloat switch (169) can be wired to open a circuit to shut off power toan electric strike (324) for the associated toilet room door (140),thereby locking the toilet room door (140). Thus, the shut-off floatswitch (169) can shut off the water supply system (170) and/or lock thetoilet room door (140) to keep the sewage-holding vault (160) fromoverflowing. Because the electric strike (324) is unlocked when it haspower and locked when it has no power, the toilet room doors (140) willalso be locked if the overall power supply system fails. As analternative to shutting off a water pump, the shut-off float switch(169) could actuate a valve, such as a solenoid valve, to shut off thewater supply system. For example, this could be done in embodimentswhere there is no water pump in the water supply system.

Power can also be supplied from the batteries (216) to the toiletcontrols (152), which control the operation of the toilets (150), and toan air compressor (330), if such an air compressor is used to supplypressurized air to the toilets (150).

The restroom system (100) and the other restroom systems discussed belowcan be constructed according to conventional building techniques, unlessotherwise noted. Standard lighting, windows, and/or skylights may beadded. Additionally, all piping, wiring and other building materials canbe conventional commercially available materials.

B. Site#2

Referring to FIGS. 6-9, Site #2 is located on a golf course where theclosest available sewer line is located at the clubhouse, which is asignificant distance away from the site. The site is not served by roadaccess, but is adjacent to a golf cart path (400), which is not designedfor heavy trucks, such as those normally used to pump toilet and septicsystems. There is no nearby potable water, but there is a non-potableburied irrigation water main (402) near the golf cart path (400). Therestroom system (410) may be exposed to periodic freezing temperatures.The site does not have good solar exposure.

The restroom system (410) can include a restroom building (412) withapproximately 80 square feet of interior space. The building (412) caninclude a floor (414), a front exterior wall (416), a pair of sideexterior walls (418), a rear exterior wall (420), and a roof (422). Thebuilding (412) can include two toilet rooms (430) that can be mirrorimages of each other. Each toilet room (430) can be defined by the rearexterior wall (420), a side exterior wall (418), the front exterior wall(416) including a toilet room door (431), and a side interior wall (432)that extends from the front exterior wall (416) back to the rearexterior wall (420), and between the floor (414) and the roof (422). Thetoilet rooms (430) can each be equipped with standard grab bars (434).Even though the toilet rooms do not have a 5-foot wheelchair turningradius, they can meet federal accessibility standards.

The building (412) can also include a mechanical room (438) between thetwo toilet rooms (430). The mechanical room (438) can be defined by theside interior walls (432) and the front and rear exterior walls (416,420) and an access door (440). The mechanical room (438) can extend fromthe floor (414) to a mechanical room ceiling (442), which divides themechanical room (438) from a mechanical room attic (444). The mechanicalroom attic (444) can be located directly above the mechanical room (438)and can be defined by the front and rear exterior walls (416 and 420),the side interior walls (432), the mechanical room ceiling (442), andthe roof (422).

The restroom building (412) can be equipped with ultra-low volume flushtoilets (450) located adjacent to the interior side wall (432) of eachtoilet room (430). Toilet operators (452), which are devices used tooperate the toilets (450), can be incorporated into the toilets (450)and/or located near to or remotely from the toilets (450). Suchoperators (452) can include a control system; a connection to anelectric power supply system; a connection to a water supply system; anda connection to a pressurized air system, such as an air compressor. Inthis embodiment, the toilets (450) can be Microphor model LF520 toiletsavailable from Microphor of Willits, Calif., and the operators (452) canbe standard operators also available from Microphor for the LF520 model.These operators (452) can be configured in a conventional manneraccording to standard techniques, such as those set forth ininstallation instructions from Microphor. Each toilet room (430) canalso house a urinal (456), such as the waterless urinals available fromWaterless Co. under the name Kalarahi model 2003. The waterless urinals(456) can be installed and configured in a conventional manner, such asby following instructions from Waterless Co. The LF520 toilet can use aslittle as one quart per flush, and it can macerate the sewage for easierpumping. The LF520 requires pressurized air, and it is fitted withpressurized air fittings, which can be served by a small air compressor(457), such as the Microphor model 5000 air compressor.

The restroom system (410) also includes a sewage storage system (458).In the illustrated example, the restroom building (412) does not have avault beneath it. Instead, the sewage storage system (458) includes asewage-holding tank (460) located near the golf cart path (400). Thesewage-holding tank (460) can be equipped with a quick-connect pump-outpipe (462). The sewage-holding tank (460) can be equipped with one ormore standard float switches to alert operators and/or disable thesystem if the sewage-holding tank (460) becomes too full. For example,the sewage-holding tank (460) can include an alert light float switch(not shown) at one level to alert an operator that the sewage-holdingtank (460) should be pumped out soon, such as by activating an indicatorlight (461). The sewage tank (460) can also include a shut-off floatswitch (not shown) at a higher level to shut down at least a portion ofa water supply system (discussed below), which is part of the restroomsystem (410), if the sewage level in the sewage-holding vault (460) istoo high. These float switches and the corresponding control wiring(466) can be the same as for Site 1, which is described above withreference to FIGS. 1-5, except that the wiring (466) extends between thesewage holding tank (460) and the restroom building (412). Thesewage-holding tank (460) can be accessed by opening an essentiallyvapor-proof manhole cover (470).

Sewage can flow to the holding tank (460) through a buried sewer line(472). Toilet drains (473) and urinal drains (474) can connect to theburied sewer line to empty urine and sewage effluent from the toilets(450) and urinals (456) into the sewer line (472). At the end of thesewer line (472) proximal to the restroom building (412), a verticalvent (475) can extend up from the sewer line (472) and through thebuilding roof (422). A cleanout riser (476) can also extend up from thesewer line (472) at the end proximal to the restroom building (412). Theslope and other design features of the sewer line (472) can be accordingto known methods, and can be done to comply with local regulations.

Sewage effluent can be removed from the sewage-holding tank (460) usinga small trailer (not shown) equipped with commercially availableequipment, including a plastic holding tank for sewage; an electricpump; a small electric generator; and a pump-out hose with a quickconnect fitting. This trailer could be towed by an ATV, light truck, ortractor to a sewer manhole at the clubhouse or to a nearby sewagetreatment facility, where it could be emptied. This trailer and itsequipment are not described in detail herein because standard equipmentcan be used.

The water supply system (480) of the restroom system (410) can include astandard valve box (482) installed on the irrigation main (402), and amain restroom water supply line (484) running from the valve box (482)to the restroom building (412). The main restroom water supply line(484) can be connected to the toilets (450) with standard restroombuilding water supply lines (486) and other standard plumbing componentsand techniques.

The restroom system (410) can also include a power supply system (510).Because the site has poor solar exposure and no convenient connectionsto grid power, the power supply system (510) can include two banks ofbatteries (514) in the mechanical room (438). Each battery can be astandard storage battery, such as an MK model 8G27 battery. Each bankcan have one or more batteries. For example, each bank can include twobatteries connected in parallel, for a total of four batteries—with twoin use, and two spares. One bank at a time can be connected to therestroom building electrical system and to a voltage meter (516). Whenthe voltage is sufficiently depleted in one bank of batteries, a personcan connect the second bank to the electrical system and the voltagemeter (516). The two partially depleted batteries can be transported tothe golf course maintenance facility for connection to a batterycharger. Once recharged, they can be returned to the restroom to serveas the spare battery bank.

The restroom system (410) can also include a frost protection system(530). The frost protection system (530) can include one or more ofseveral components to protect the restroom system (410) from freezingtemperatures. For example, the frost protection system (530) can includebuilding insulation (531) in the exterior walls (416, 418, and 420) andthe roof (422); insulation around plumbing equipment; and/or water lines(486) that do not break when frozen.

As another example, the frost protection system (530) can include apassive ventilation system that brings air into the building (412) usingventilation air with temperatures moderated through heat exchanged fromthe earth below the building (412) circulated as follows: air is draftedup the flue stack (533) having flowed from the mechanical room attic(444) through a flue-to-attic grill (534) in the rear exterior wall(420); having flowed from the toilet rooms (430) to the mechanical roomattic (444) through a pair of ventilation grills (536) located in theside interior walls (432); having flowed from the mechanical room (438)to the toilet rooms (430) through ventilation openings (560) in eachtoilet's (450) metal housing and through the interior space between eachtoilet's (450) metal outer housing and inner metal toilet bowl andthrough the mechanical access hole (562) at the back of each toilet(450) in the mechanical room wall (432); having flowed from the outsidethrough floor grates (568) in the restroom's floor slab (414) through aventilation pipe manifold (570) in the ground below the building (412).The ventilation pipe manifold (570) can be used if there is no watertank below the building to transfer earth temperatures to the supplyair, as there is at Site #1. The ventilation pipe manifold (570) can beperforated to allow moisture to escape, such as by draining throughperforations in the bottom of the manifold pipe (570).

During use, the ventilation system (532) at Site #2 can work the same asthe ventilation system (232) described above with reference to Site #1,except that the intake air can flow through the buried ventilation pipemanifold (570), rather than through a plenum beneath a water vault, andthe damper and the associated ductwork, grills, and activator can beomitted.

The electrical components for the restroom system (410) at Site #2 canbe similar to the electrical components described above for restroomsystem (100) at Site #1, with reference to FIG. 5.

C. Site#3

Referring to FIG. 10, Site #3 is a lakeside day-use county park in aremote location. Site, environmental, and soil conditions make theinstallation of an on-site septic drain field impractical. However,there is a good site for a septic drain field on county land a mileaway. The county wishes to construct two restroom buildings located nearan access road (600). Each building is to have a men's and women'srestroom with multiple stalls and wash sinks. There is a nearby spring(604) that can provide adequate flush water and has enough elevation tosupply the pressure head needed to flush the toilets. (Water could havebeen supplied by a submersible pump placed in the lake, but the springsource was considered the better option in this particularcircumstance.) Both preferred restroom locations have large trees thatinhibit the use of solar panels on the buildings. The climate is mildduring the use season and freezing is not an issue. The water in thesystem will be drained during the winter months.

Considering these desired features and site conditions, a restroomsystem (610) can include two similar restroom buildings (612). Therestroom buildings (612) can each have a men's side (614) and a women'sside (616), and each can house multiple ultra-low volume flush toilets(618) and urinals (620), as well as sinks (622) and an external coldwater shower (624). The toilets (618) and urinals (620) can be the sameas the toilets and urinals discussed above with reference to Site #1and/or Site #2. The restroom buildings can be constructed according tostandard building construction techniques.

The restroom system (610) can include a water supply system (630), whichcan include buried water lines (632) running from a collection boxlocated at the spring (604) to the restroom buildings (612), and afiltered water purification system such as a Pentek CBC-20 (not shown).The restroom system (610) can also include a power supply system (640)that includes a solar collector (642), including a standard solar arrayand a mast located near the access road (600) where there is good solarexposure. The power supply system (640) can also include buriedelectrical cables (644) connected to the solar collector (642) and tothe restroom buildings (612) in a conventional manner.

In addition, the restroom system (610) includes a sewage storage system(650). The sewage storage system (650) can include buried sewer lines(652) extending from the restroom buildings (612) to a junction manhole(654), and from the junction manhole (654) to a single largesewage-holding tank (656) located near the road (600) where there issufficient drop from the restroom buildings (612) to the holding tank(656) for the sewage effluent to flow by the force of gravity throughthe sewer lines (652). The holding tank (656) can be equipped with anaccess cover (660) and a pump-out pipe (662).

Because freezing is not an issue at this site during the use season,ventilation into the toilet rooms and mechanical room can be provided bystandard site proof wall and door grills (not shown). The restrooms canbe locked at dusk so that no building lighting is needed.

The electrical components for the restroom system (610) at Site #3 canbe similar to the electrical components described above for the restroomsystem (100) at Site #1, with reference to FIG. 5. However, oneelectrical system can power the indicator light and toilet controls inboth restroom buildings (612), and there is no need for a thermostatswitch, water pump, or a damper controller. An upper shut-off floatswitch (not shown) can prompt a valve actuator, such as a solenoid, toshut off water to the toilets (618), such as by shutting off water tothe entire buildings (612), if the sewage-holding tank (656) gets toofull.

D. Site #4

Site #4 had an existing precast concrete vault toilet restroom buildingoriginally manufactured by CXT Inc., model “Double Cascadian withChase”, which has approximately 96 square feet of interior space and islocated at a site with good solar exposure and adequate rainfall. TheseCXT units include four buried precast concrete vaults placed directlyunder the precast concrete building unit. The CXT units have twoidentical vaults for sewage holding. The other two vaults are empty andunused, but are an appropriate size to serve as water holding vaults.

FIGS. 11-15 show the details of a restroom system (800) formed byretrofitting a CXT vault toilet restroom building. Retrofitting couldalso be done with other restroom buildings, such as other CXT buildingsor other non-CXT vault or composting toilet buildings. The finishedrestroom system (800) will be described first, and a retrofittingtechnique will be described second.

The illustrated restroom system (800) can include a building (802) withabout 96 square feet of interior space, although many differentconfigurations and/or sizes of restroom buildings could be retrofitted.The building (802) can include a floor (804), a front exterior wall(806), a pair of side exterior walls (808), a rear exterior wall (810),and a roof (812).

The building (802) can include two toilet rooms (820) that can be mirrorimages of each other. Each toilet room (820) can be defined by the rearexterior wall (810); a side exterior wall (808); the front exterior wall(806); a side interior wall (822), which extends from the front exteriorwall (806) back to the rear exterior wall (810) and between the floor(804) and the roof (812). The toilet rooms (820) can each be equippedwith standard grab bars (824).

The building (802) can also include a mechanical room (828) between thetwo toilet rooms (820). The mechanical room (828) can be defined by theside interior walls (822) and the front and rear exterior walls (806,810). The mechanical room (828) can extend from the floor (804) to amechanical room ceiling (832), which divides the mechanical room (828)from a mechanical room attic (834). The mechanical room attic (834) canbe located directly above the mechanical room (828).

The building (802) can also include toilet room doors (840) in the frontexterior wall (806) and a mechanical room door (842) in the rearexterior wall (810). In addition, the building (802) can include ceilinginsulation (844) in the mechanical room ceiling (832), as well asmechanical room wall insulation (846) on the side interior walls (822)in the mechanical room (828).

Openings in the floor (804) for the original vault toilet risers can becovered with metal plates (848), equipped with sealed openings toaccommodate the septic pipes exiting the bottom of each toilet (850). Asan alternative these existing floor opening could be filled in withconcrete plugs. Each toilet room (820) can house an ultra-low volumeflush toilet (850) located adjacent to the interior side wall (822) ofthe toilet room (820). Toilet operators or controls (852) can beincorporated into the toilets (850) and/or located near to or remotelyfrom the toilets (850). Such operators (852) can include a controlsystem; a connection to an electric power supply system; and aconnection to a water supply system. In this embodiment, the toilets(850) can be Microphor model LF320 toilets available from Microphor ofWillits, Calif., and the operators (852) can be standard operators alsoavailable from Microphor for the LF320 model. These operators (852) canbe configured in a conventional manner according to standard techniques,such as those set forth in installation instructions from Microphor.

Water lines can extend from each toilet (850) and through an access hole(854) located behind each toilet (850) in the associated side interiorwall (822) into the mechanical room (828). Each toilet room (820) canalso house a urinal (856), such as the waterless urinals available fromWaterless Co. under the name Kalarahi model 2003. The waterless urinals(856) can be installed and configured in a conventional manner, such asby following instructions from Waterless Co. The LF320 toilet can use aslittle as one quart per flush.

The restroom system (800) also includes a sewage storage system (858),which can include one or more sewage-holding vaults (860). In theillustrated example, the sewage storage system (858) includes oneexisting subterranean sewage-holding vault (860) for each toilet room(820), with the vault positioned beneath the rear portion of theassociated toilet room (820). Each toilet (850) and urinal (856) can beconfigured to drain into the associated sewage-holding vault (860) sothat the vault (860) receives the sewage effluent from that associatedtoilet room (820). Alternatively, the restroom system (800) couldinclude just one sewage-holding vault (860), and it could be locatedsomewhere other than beneath the building (802).

Each sewage-holding vault (860) can be a subterranean precast concretesewage-holding vault (860), which may or may not be equipped with aplastic liner (862) to seal the vault. A sewage-holding vault accesscover (863) can be opened to provide access to each sewage-holding vault(860). The sewage storage system (858) can also include standard sewagepump-out piping (864) that is configured to mate with sewage pump-outequipment associated with a sewage transportation vehicle. Eachsewage-holding vault (860) can be vented by a small vertical pipe (865)that extends up from the sewage-holding vault (860) and through the roof(812) of the building (802). A toilet drain (866) can extend down fromeach toilet (850) to the corresponding sewage-holding vault (860), and aurinal drain (867) can extend down from each urinal (856) to thecorresponding sewage-holding vault (860).

Each sewage-holding vault (860) can be equipped with one or morestandard float switches to alert operators and/or disable the system ifthe sewage-holding vault (860) becomes too full. For example, eachsewage-holding vault (860) can include an alert float switch (868) atone level to alert an operator that the sewage-holding vault (860)should be pumped out soon. Each sewage-holding vault (860) can alsoinclude a shut-off float switch (869) at a higher level to shut down atleast a portion of a water supply system (870), which is part of therestroom system (800), if the sewage level in the sewage-holding vault(860) is too high. These float switches and the corresponding controlcircuitry can be similar to the float switches and circuitry describedabove with reference to Site #1.

The water supply system (870) can supply pressurized water to thetoilets (850). The water supply system (870) can include water storagevaults (872) beneath each of the toilet rooms (820), such as theexisting subterranean water storage vaults (872) which may be equippedwith an impermeable liner or coating (873). A rainwater collectionsystem (874) can include standard rain gutters (876), as well asstandard downspouts (878) leading into the water storage vaults (872).The water supply system (870) can also include water fill piping (880),which can be standard piping for receiving additional water tosupplement collected rainwater. For example, the water fill piping (880)can be configured to connect to a water hauling vehicle.

The water supply system (870) can also include a water pressurizationsystem (882) that includes a water pump (884) that is connected to drawwater from the water storage vault (872) and feed it into an accumulatortank (886), which is connected to the toilets (850) to supplypressurized water to the toilets (850). The water pump can be a standardwater pressurizing pump, such as a “Classic 2088” water pump availablefrom Shurflo, and the accumulator tank can be a standard tank, such as a3400-002 tank available from Shurflo.

In addition, the water storage vaults (872) can have drains (890) highon their side walls that allow excessive rainwater or filling waterinflows to spill out of the vault, thus preventing overfilling of thewater storage vault (872). The drains (890) can extend through the sameholes in the water storage vault (872) through which the downspouts(878) enter the water storage vault (872). The water supply system (870)also includes water lines (892) that connect the various othercomponents of the water supply system.

The restroom system (800) can also include a power supply system (910)that includes a solar panel (912), such as the model GEPV-50 solar panelavailable from General Electric. The power supply system can alsoinclude a controller (914), such as the 12 volt, 15 amp controllerequipped with a digital voltage meter available from Prostar. The powersupply system can also include one or more standard storage batteries(916), such as two MK model 8G27 storage batteries. The storagebatteries (916) can be connected to be recharged by the solar panel(912), and to supply the power needs of the restroom system (800) in aconventional manner. The solar panel (912) can be mounted on top of aflue stack (918) that extends up along the rear exterior wall (810). Forexample, the solar panel (912) can be mounted with a rotatable base(920), which allows a user to pivot the solar panel (912) to face in adesired direction (such as south when in the northern hemisphere) nomatter what the building orientation is.

The restroom system (800) can include a frost protection system (930).The frost protection system (930) can include one or more of severalcomponents to protect the restroom system (800) from freezingtemperatures. For example, the frost protection system (930) can includebuilding insulation (844, 846) attached to the mechanical room walls(822) and ceiling (832); insulation around plumbing equipment such asthe water pump (884) and the accumulator tank (886); and/or water lines(892) that do not break when frozen.

As another example, the frost protection system (930) can include aventilation system (932) that controls the circulation of air into thebuilding (802). This ventilation system (932) can include the fluestacks (918), which are vented into the toilet rooms (820) throughflue-to-toilet room grills (934) in the rear exterior wall (810),existing vents in the exterior walls (935), ventilation grills (936)located in the metal bases of the toilets (850), floor grates (937) inthe mechanical room floor (804), and the rain collection downspouts(878).

During use, the ventilation for the restroom building (802) can bepassively enhanced by the influence of the wind blowing over the openingof the flue stack (918) due to the venturi effect which can createnegative pressure in the stack (918). As interior air exits the stack(918) makeup air from the interior of the building (802) flows throughthe associated flue-to-toilet room grill (934); having flowed from thetoilet rooms (820); having flowed from the mechanical room (828) throughventilation openings (936) in each toilet's (850) metal housing andthrough the interior spaces between each toilet's (850) metal baseexterior and the inner metal toilet bowl and through the mechanicalaccess hole (854) at the back of each toilet (850) in the mechanicalroom wall (822); having flowed from the outside through floor grates(937) in the restroom's floor slab (804); having flowed through the airspace above the water in the water storage vault (872); having flowedthrough the building's rain down spouts (878). Outside air can also flowinto the toilet rooms (820) through the existing vents (935) located atthe bottom of the side and back exterior walls (808, 810). These ventscan be retrofitted with bug screens or filters to inhibit airflow enoughthat airflow priority is always given to the air exiting the base of thetoilets having traveled a path of lesser resistance and having beenconditioned by the influence of ground temperatures surrounding thein-ground water storage vault.

In addition, when the temperature of some point within the building(802), such as the water within the toilet bowls falls below a setpoint, the toilets (850) can automatically flush to replace the water inthe toilet bowls with warmer water from the water storage vault (872).This automatic flushing feature will be described more below.

The electrical components for the restroom system (800) at Site #4 canbe basically the same as the electrical components described above forrestroom system (100) at Site #1, with reference to FIG. 5. However,there is no 12 VDC to 24 VDC Converter (308), or Vent Damper Controller(310), or Air Compressor (330).

Referring to FIG. 15, a schematic illustrates the components to make thetoilet (850) automatically flush when the water in the toilet bowl dropsclose to freezing. A standard manual flush switch (852) can send a pulsesignal to the toilet controls (1105), resulting in commencement of theflush cycle when a user manually actuates the switch (852) or when theswitch (852) is tripped by a motion sensor, depending on the embodiment.A temperature sensor (1100) can be affixed to the bottom of the bowl ofeach toilet (850). Leads from the temperature sensors (1100) can beconnected to a temperature controller (1110). When one of the sensors(1100) reports temperatures near freezing, the controller (1110) canactivate a relay switch (1120), which can send a pulse signal to theassociated toilet controls (1105), resulting in commencement of theflush cycle. The signal between the controller (1110) and the relayswitch (1120) can be moderated by a delay timer (1130). The delay timer(1130) can prevent subsequent automatic flushing pulses from beingtransmitted to the toilet controls (1105) until enough time has passedto allow the metal toilet bowl to warm to a temperature at or near thetemperature of the water in the bowl. Referring to FIGS. 11-15, as analternative to or in addition to automatic flushing, the temperaturesensors (1100) and the temperature controller (1110) can be wired toopen a circuit to shut off power to an electric strike (such as thestrike (324) discussed above and illustrated in FIG. 5) for theassociated toilet room door (840), thereby automatically locking thetoilet room door (840). This can be done when one of the sensors (1100)reports freezing temperatures (i.e., temperatures that indicate water inthe system could be frozen, such as temperatures at a predeterminedlevel near, at, or below freezing). Some other temperature sensor, suchas a thermostat within the restroom building (802) could be used insteadof the temperature sensors (1100) affixed to the toilet bowls. Thisautomatic door lock feature can keep users from continuing to use therestroom system (800) while water in the restroom system is frozen. Asis discussed herein, the equipment in the restroom system (800) can bedesigned to survive freezing water, such as by including elastomericwater lines (892) that can withstand freezing water, and having asubmersible water pump that is submerged in the water tank (872) to helpavoid freezing of the water pump.

Retrofitting an existing precast vault restroom building to convert itinto the restroom system (800) with ultra-low volume flush toilets willnow be described. The precast house can be lifted or jacked off theexisting precast vaults below so that impermeable liners or coatings(873) can be installed in the unused chambers under the front of thebuilding for service as water storage tanks (872). The unused chambersin the existing precast vaults may be used as water storage vaults (872)without applying sealants or installing liners if these chambers arefound to be water-tight. If this is the case, lifting or jacking up theexisting building (802) can be avoided by sealing the drains located inthe floor of the unused vault chambers with a non-shrink grout placedthrough a hole drilled in the floors (804) of the toilet rooms (820).These drilled holes can be filled in or fitted with a cover plate afterthe grouting operation. As an alternative to using the existing unusedchambers, a new water storage tank can be placed outside of the existingbuilding's footprint. The existing sewage-holding vaults (860) typicallywill not require modification, except that they can be equipped withfloat switches (868 and 869), which can be hung from the bottom of thecover plate (848). The electrical wiring for the float switches can berouted through a hole in the cover plate (848), through the base of thetoilets (850) into the mechanical room (828). Holes can be core drilledthrough the floor (804) of the building (802) above the sewage-holdingvaults (860) to add the quick-connect pump-out pipe (864), athrough-the-roof vent (865), and urinal drains (867). The restroombuilding (802) can be equipped with the electrical and plumbingequipment discussed above, including the toilets (850), water pump(884), accumulator tank (886), solar panel (912), controller (914), andstorage batteries (916). The existing flue stacks can be replaced withstacks (918) of the same dimensions, except that the flue stacks (918)can have airtight seals at their bottoms and be equipped with a sidevent corresponding to the flue-to-toilet room grill (934). One fluestack (918) can have the solar panel (912) attached to a rotatablemounting (920) at the top. Holes can be drilled through the roof (812)and ceiling of the mechanical room (832) for running the electricalcables serving the solar panel (912).

Holes can be core-drilled through the floor above the water storagevault for the addition of water fill pipes (880), and water lines (892).The outside walls of each water storage tank (872) can be cored or cutto allow penetration of the downspouts (878) of the rainwater collectionsystem (874). These openings can also serve as overflow drains for thewater storage tank (872). Access holes (854) for the toilets (850) canbe cut out of the side interior walls (822) behind the toilets (850) toallow access for water supply lines (892).

A ceiling (832) can be installed above the mechanical room (828).Ceiling insulation (844) can be applied to the mechanical room ceiling(832). Mechanical room wall insulation (846) can be applied to the sideinterior walls (822) in the mechanical room (828). Further, insulatedwall panels and insulated ceilings (not shown) can be added to thetoilet rooms (820). The building's (802) restroom doors (840 and 842)can be insulated and fitted with weather-stripping and thresholds toreduce undesirable airflow. The water lines (892) in the mechanical room(828) can be elastomeric to inhibit breaking if water in the water lines(892) freezes. The existing sewage waste tank access holes and covers(863) can remain unchanged. The existing floor openings for the vaulttoilet riser are shown being closed off with a sealed cover (848), whichcan be a plate or the floor openings could be filled with doweledconcrete plugs or covered in some other manner. Lighting could be added(not shown).

IV. Techniques for Making and Using Restrooms

Referring to FIG. 16, general techniques relating to fixed-in-placestand-alone flush restroom systems will be described. A restroom system,such as one of the restroom systems (100, 410, 610, 800) described aboveor some other restroom system, can be provided (1200). Sewage can bereceived (1210) one or more times in the restroom system, and a toiletcan be flushed (1220) one or more times. The sewage effluent can betransported (1230) to a sewage-holding vessel, such as a tank or vault.The effluent can be extracted (1240) from the vessel to a sewage haulingvehicle, such as by pumping, and can be transported (1250) in the sewagehauling vehicle.

Referring to FIG. 17, providing a flush restroom system can includeretrofitting an existing vault or composting toilet system. This caninclude replacing (1300) a vault or composting toilet with a flushtoilet, connecting (1310) the toilet to a water supply, and connecting(1320) the flush toilet restroom system to a power supply. The flushtoilet can also be connected (1330) to a source of pressurized air.

While the invention has been particularly shown and described withreference to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of theinvention.

1. A method comprising: receiving sewage in a flush toilet in a restroomsystem, the restroom system comprising: a fixed-in-place restroombuilding; a flush toilet housed in the restroom building; a water supplysystem in communication with the flush toilet; and a sewage-holdingvessel in communication with the flush toilet; supplying water from thewater supply system to the flush toilet in an amount less than 1 gallonof water per flush; and transporting sewage effluent from the flushtoilet to the holding vessel.
 2. The method of claim 1, wherein themethod further comprises automatically locking one or more doors in therestroom building when freezing temperatures are sensed within therestroom system.
 3. The method of claim 1, wherein the method comprisesnon-residential use of the restroom system.
 4. The method of claim 1,further comprising: extracting the sewage effluent from thesewage-holding vessel and to a sewage hauling vehicle tank; andtransporting the sewage effluent in the sewage hauling vehicle tank. 5.The method of claim 1, wherein the restroom system further comprises awaterless urinal in communication with the sewage-holding vessel.
 6. Themethod of claim 1, wherein the restroom system further comprises anelectric power supply system.
 7. The method of claim 1, whereintransporting sewage effluent from the flush toilet to the holding vesselcomprising introducing pressurized air to the sewage effluent.
 8. Themethod of claim 1, wherein supplying water from the water supply systemcomprises pressurizing the water.
 9. The method of claim 1, furthercomprising retrofitting an existing vault toilet restroom building withthe flush toilet to provide the restroom system.
 10. The method of claim1, wherein the restroom system inhibits freezing of water in therestroom building.
 11. The method of claim 1, wherein the restroomsystem inhibits freezing of water in the restroom building by passingair through a passage wherein the air absorbs heat from the groundbefore entering the restroom building.
 12. The method of claim 1,wherein the restroom system inhibits freezing of water in the restroombuilding by automatically flushing a toilet.
 13. The method of claim 1,wherein the restroom system inhibits freezing of water in a bowl of thetoilet by circulating air through a base of the toilet.
 14. The methodof claim 1, wherein the restroom system inhibits freezing of water inthe restroom building by enhancing circulation of air using a fluestack.
 15. The method of claim 1, wherein the restroom system inhibitsfreezing of water in the restroom building by decreasing circulation ofexternal air through the restroom building during times when an externaltemperature drops below a predetermined low temperature.
 16. The methodof claim 1, wherein the restroom system inhibits overflow of sewage fromthe holding vessel.
 17. The method of claim 1, wherein the restroomsystem directs air through a ventilation system in the restroombuilding.
 18. The method of claim 1, wherein the restroom system doesnot include septic treatment features.
 19. A method comprising:retrofitting an existing vault or composting toilet restroom system withone or more flush toilets to produce a flush toilet restroom system, theretrofitting comprising: replacing a vault or composting toilet riserhoused in a fixed-in-place restroom building with a flush toilet that isdesigned to use less than one gallon of liquid per flush in thefixed-in-place restroom building, the flush toilet being incommunication with a sewage-holding vessel that was previously incommunication with the vault or composting toilet riser; connecting awater supply system to the flush toilet; and connecting a power supplysystem to the flush toilet restroom system.
 20. The method of claim 19,wherein the method further comprises automatically locking one or moredoors in the flush toilet restroom system when freezing temperatures aresensed within the flush toilet restroom system.
 21. The method of claim19, wherein the method further comprises non-residential use of therestroom system.
 22. The method of claim 19, wherein the vault orcomposting toilet restroom system is a vault toilet restroom system, andwherein the vault or composting toilet riser is a vault toilet riser.23. The method of claim 19, wherein the vault or composting toiletrestroom system is a composting toilet restroom system, and wherein thevault or composting toilet riser is a composting toilet riser.
 24. Themethod of claim 19, further comprising installing a waterless urinal incommunication with the sewage-holding vessel.
 25. The method of claim19, further comprising: receiving sewage in the flush toilet; flushingthe flush toilet, the flushing comprising supplying water from the watersupply system to the flush toilet in an amount less than 1 gallon ofwater per flush; transporting sewage effluent from the flush toilet tothe holding vessel; extracting the sewage effluent out of thesewage-holding vessel and to a sewage hauling vehicle tank; andtransporting the sewage effluent in the sewage hauling vehicle tank. 26.The method of claim 19, further comprising connecting the flush toiletto a source of pressurized air.
 27. The method of claim 19, wherein thewater supply system pressurizes water supplied to the flush toilet. 28.The method of claim 19, wherein the flush toilet restroom systeminhibits freezing of water in the restroom building.
 29. The method ofclaim 19, wherein the flush toilet restroom system inhibits freezing ofwater in the restroom building by passing air through a passage whereinthe air absorbs heat from the ground before entering the restroombuilding.
 30. The method of claim 19, wherein the flush toilet restroomsystem inhibits freezing of water in the restroom building byautomatically flushing a toilet.
 31. The method of claim 19, wherein theflush toilet restroom system inhibits freezing of water in the restroombuilding by decreasing circulation of external air through the restroombuilding during times when an external temperature drops below apredetermined low temperature.
 32. The method of claim 19, wherein theflush toilet restroom system inhibits freezing of water in a bowl of theflush toilet by circulating air through a base of the flush toilet. 33.The method of claim 19, wherein the restroom system inhibits freezing ofwater in the restroom building by enhancing circulation of air using aflue stack.
 34. The method of claim 19, wherein the flush toiletrestroom system inhibits overflow of sewage from the holding vessel. 35.The method of claim 19, wherein the flush toilet restroom systemcomprises a ventilation system.
 36. The method of claim 19, wherein theflush toilet restroom system does not include septic treatment features.37. A restroom system comprising: a fixed-in-place restroom building; aflush toilet housed in the restroom building, the flush toilet designedto use less than 1 gallon of water per flush; a water supply systemconnected to supply water to the flush toilet; and a sewage-holdingvessel in communication with the flush toilet to receive sewage effluentfrom the flush toilet, the sewage-holding vessel including an outlet forextracting sewage effluent from the sewage-holding vessel.
 38. Therestroom system of claim 37, wherein the restroom system is configuredto automatically lock one or more doors in the restroom system whenfreezing temperatures are sensed within the restroom system.
 39. Therestroom system of claim 37, wherein the restroom system is in anon-residential setting.
 40. The restroom system of claim 37, furthercomprising a waterless urinal in communication with the sewage-holdingvessel.
 41. The restroom system of claim 37, further comprising a powersystem configured to supply electric power to the restroom system. 42.The restroom system of claim 37, further comprising an air pressurizingsystem configured to supply pressurized air to assist in moving sewageeffluent to the sewage-holding vessel.
 43. The restroom system of claim37, wherein the restroom building houses a waterless urinal incommunication with the sewage-holding vessel.
 44. The restroom system ofclaim 37, wherein the flush toilet is a first flush toilet and therestroom houses the first flush toilet and a second flush toiletdesigned to use less than 1 gallon of water per flush, the second flushtoilet being in communication with the sewage-holding vessel so that thesewage-holding vessel receives sewage effluent from the first flushtoilet and the second flush toilet.
 45. The restroom system of claim 37,wherein the water supply system comprises a water-holding vessel. 46.The restroom system of claim 37, wherein the water supply systemcomprises a water pressurizing system.
 47. The restroom system of claim37, wherein the restroom building is a vault toilet restroom buildingthat has been modified for use with the flush toilet.
 48. The restroomsystem of claim 37, comprising means for inhibiting freezing of water inthe restroom building.
 49. The restroom system of claim 37, wherein therestroom system is configured to inhibit freezing of water in therestroom building by passing air through a passage wherein the airabsorbs heat from the ground before entering the restroom building. 50.The restroom system of claim 37, wherein the restroom system isconfigured to inhibit freezing of water in the restroom building byautomatically flushing the flush toilet.
 51. The restroom system ofclaim 37, wherein the restroom system is configure to inhibit freezingof water in the restroom building by decreasing circulation of externalair through the restroom building during times when an externaltemperature drops below a predetermined low temperature.
 52. Therestroom system of claim 37, wherein the restroom system is configuredto inhibit freezing of water in a bowl of the flush toilet bycirculating air through a base of the toilet.
 53. The restroom system ofclaim 37, wherein the restroom system is configured to inhibit freezingof water in the restroom building by enhancing circulation of air usinga flue stack.
 54. The restroom system of claim 37, comprising means forinhibiting overflow of sewage from the holding vessel.
 55. The restroomsystem of claim 37, further comprising a restroom ventilation system.56. The restroom system of claim 37, wherein the restroom system doesnot include septic treatment features.